The present invention relates to an electric primer for caseless propellant charges and the like, which are optionally also firmly connected with a projectile, wherein the primer which is, if desired, arranged on a support, has an electrically conductive layer. The layer contains an electrically conductive material and an explosive. The invention furthermore relates to a process for the manufacture of such primers and, finally, to propellant charges provided with an electric primer.
In addition to percussion, frictional, and flash primers, the electric primers, which have been known for a long time, have gained an ever-increasing importance.
Electric bridge primers and also gap primers have proven themselves well, particularly in conventional cartridges for machine firearms and initiator blasting caps. Layered primers wherein the electric conductors consist of graphite or metallic layers require a very high ignition current, which limits their applicability. The use of electric primers for caseless propellant charges, which has recently been made feasible, posed quite special requirements for the primers. The main requirements are the following: Above all, such a primer must not cause or form any deposits on the electrodes. The ignition must be possible with low ignition currents, and this ignition must be reliably obtainable. The primer should be combusted with a minimum of residue. Furthermore, such a primer should exhibit low sensitivity against shock and friction, as well as against static electricity and currents which lie below the desired ignition threshold.
The following description relates to a primer and its manufacture, the primer fulfilling the requirements for use in caseless cartridges and propellant charges and thus utilizable in conventional cartridges and initiator blasting caps, as well as for caseless cartridges and propellant charges.